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I was at Lowes today and saw a solar powered attic fan. 850cfm for 1200sqft. The vents I have now are those cheapo mushroom headed looking rascals. I live in Texas and my attic is hotter than Satan's armpit. What's the verdict. $368 a good investment or a waste?

Conventional attic power vents cost very little to operate and can move twice as much air as the solar fans. You will never make back the first cost difference with the solar unit. The exception might be if adding electric service to your attic would be expensive - if, say, the furnace circuit is the only one up there now. (Since that's a single-appliance circuit, you can't legally add anything else to it.)

Solar - *might* mean you don't need a permit, or you might need a building/appliance permit. Permits for solar equipment are no-fee in many areas too. Note that despite the manufacturer's claims, this is still an electrical device and some jurisdictions might still want a "low voltage" electrical permit. Keep in mind that you will need to install two solar fans to move as much air as one conventional fan, and that solar fans don't work when the sun isn't shining.

Conventional - you will almost definitely need an electrical permit, possibly in addition to the building/appliance permit. Add permit fees on top of the cost of providing a legal branch circuit to the fan. Often those costs will be minimal, sometimes they will be substantial. In most cases, the conventional fan will probably end up being cheaper - and it runs all the time when the attic's hot enough to need it, not just when there's direct sunlight available.

If you have an asphalt shingle roof, have a roofer come buy and install a full ridge vent along all your ridges
(cobra etc.).
These type of vents have proven to be the most effecient and if your soffit venting is adequate natural convection will force the hot air out!

Yep - but I understand there are issues with getting enough ridge length for hip roofs, as well as draft-bypassing if you have multiple-level peaks. A draft can be created that makes the lower peak's ridge vent an intake and the upper ridge vent as the outlet - which can really cut down on the intake at the soffit level.

I was put off by the high cost also, until I found a solar fan for 50 at HD and a solar panel for 50 at HD (you can add more panels if you want more speed- nice feature)

So for 100 I got a fan than runs for free, operates at a closer to proper speed (meaning any 120v fan pulled WAY too much- would have caused problems) and runs when the wind is not blowing- which often happens in the hottest parts of the day around here (DFW).

The current units, like most items now, are poorly made! My elec lasted 2wk from Lowes in 2000 = $100 -- fan shook loose from bracket & jammed = motor shot! then blowing rain came in since top hat was not large enuf. I had tin- knocker put a 1" skirt on hat to stop rain & now just let gravity remove air out of attic of 2nd level. --